Low power ring detect for computer system wake-up

Abstract

A computer system having a CPU, a power management processor, a modem, and a power supply in circuit communication. The power management processor controls the regulation of power to the CPU by the power supply. Responsive to a ring signal having a frequency in a predetermined range being detected by the power management processor, the power management processor causes the power supply to provide regulated power to the computer system. Thereafter, the CPU confirms that a ring signal was present by querying the modem whether the modem also detected a ring. If so, the system remains powered. If not, the CPU causes the power management controller to cause the power supply to cease providing regulated power.

What is claimed is: 
     
       1. A computer system comprising: (a) a CPU;   (b) a power management processor in circuit communication with said CPU;   (c) a modem in circuit communication with said power management processor via a ring signal line and in circuit communication with said CPU, for being placed in circuit communication with a telephone line, and characterized by generating a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line;   (d) a power supply in circuit communication with said CPU and said power management processor comprising circuitry for selectively providing system power to said CPU responsive to said power management processor, characterized by having a first power supply state and a second power supply state, and further characterized by having circuitry for providing auxiliary power to said power management processor; wherein said first power supply state is characterized by said power supply providing system power to said CPU and providing auxiliary power to said power management processor; and   wherein said second power supply state is characterized by said power supply not providing system power to said CPU and said power supply providing auxiliary power to said power management processor;     (1) wherein said power management processor is further characterized by causing said power supply to transition from said first power supply state to said second power supply state responsive to at least one of a first predetermined plurality of conditions;   (2) wherein said power management processor is further characterized by causing said power supply to transition from said second power supply state to said first power supply state responsive to at least one of a second predetermined plurality of conditions;   (3) wherein one of said second predetermined plurality of conditions comprises a ring signal being communicated from said modem to said power management processor; and   (4) wherein said power management processor is further characterized by analyzing the frequency of the ring signal generated by said modem and wherein one of said second predetermined plurality of conditions comprises a ring signal having a frequency in a predetermined range being communicated from said modem to said power management processor.   
     
     
       2. A computer system according to claim 1 wherein: (a) said modem is an internal modem that generates a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line even when said modem is not powered;   (b) said first power supply state is characterized by said power supply providing system power to said CPU and said modem and providing auxiliary power to said power management processor; and   (c) said second power supply state is characterized by said power supply not providing system power to said CPU or said modem and said power supply providing auxiliary power to said power management processor.   
     
     
       3. A computer system according to claim 1 wherein said CPU queries said modem whether said modem detects a ring signal responsive to said power management processor causing said power supply to transition from said second power supply state to said first power supply state because said power management processor detected a ring signal and, responsive to said modem not detecting a ring signal, said CPU causing said power management processor to cause said power supply to transition from said first power supply state to said second power supply state. 
     
     
       4. A computer system comprising: (a) a CPU;   (b) a power management processor in circuit communication with said CPU;   (c) a modem in circuit communication with said power management processor via a ring signal line and in circuit communication with said CPU, for being placed in circuit communication with a telephone line, and characterized by generating a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line;   (d) a power supply in circuit communication with said CPU and said power management processor comprising circuitry for selectively providing system power to said CPU responsive to said power management processor, characterized by having a first power supply state and a second power supply state, and further characterized by having circuitry for providing auxiliary power to said power management processor; wherein said first power supply state is characterized by said power supply providing system power to said CPU and providing auxiliary power to said power management processor; and   wherein said second power supply state is characterized by said power supply not providing system power to said CPU and said power supply providing auxiliary power to said power management processor;     (e) a non-volatile storage device in circuit communication with said CPU, said non-volatile storage device having stored therein a state of said computer system while said power supply is in said second power supply state; and   (1) wherein said power management processor is further characterized by causing said power supply to transition from said first power supply state to said second power supply state responsive to at least one of a first predetermined plurality of conditions;   (2) wherein said power management processor is further characterized by causing said power supply to transition from said second power supply state to said first power supply state responsive to at least one of a second predetermined plurality of conditions;   (3) wherein one of said second predetermined plurality of conditions comprises a ring signal being communicated from said modem to said power management processor; and   (4) wherein, before the state of said computer system is read from said non-volatile storage device responsive to said power supply transitioning from said second power supply state to said first power supply state, said CPU queries said modem whether said modem detects a ring signal and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.   
     
     
       5. A computer system according to claim 4 wherein: (a) said modem is an internal modem that generates a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line even when said modem is not powered;   (b) said first power supply state is characterized by said power supply providing system power to said CPU and said modem and providing auxiliary power to said power management processor; and   (c) said second power supply state is characterized by said power supply not providing system power to said CPU or said modem and said power supply providing auxiliary power to said power management processor.   
     
     
       6. A computer system having at least two modes of power management, namely (i) a normal operating mode in which code is executed normally by the computer system, (ii) a power conservation mode in which the computer system consumes less electrical power than in said normal operating mode, said computer system comprising: (a) a CPU;   (b) a power management processor in circuit communication with said CPU, said power management processor causing transitions between said at least two modes of power management;   (c) a modem in circuit communication with said power management processor via a ring signal line and in circuit communication with said CPU, said modem for being placed in circuit communication with a telephone line, and said modem characterized by generating a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line;   (d) a non-volatile storage device in circuit communication with said CPU, said non-volatile storage device having stored thereon the state of said computer system while said computer system is in said power conservation mode; and   (e) a power supply in circuit communication with said CPU and said power management processor, said power supply having circuitry for selectively providing system power to said CPU responsive to said power management processor and having auxiliary circuitry for providing auxiliary power to said power management processor, said power supply characterized by having a first power supply state and a second power supply state; wherein said first power supply state is characterized by said power supply providing system power to said CPU and providing auxiliary power to said power management processor; and   wherein said second power supply state is characterized by said power supply not providing system power to said CPU and said power supply providing auxiliary power to said power management processor;     (1) wherein transitioning from said power conservation mode to said normal operating mode includes said power management processor changing said power supply from said second power supply state to said first power supply state and, thereafter, reading the state of said computer system from said non-volatile storage device;   (2) wherein said power management processor analyzes the frequency of a ring signal generated by said modem;   (3) wherein said power management processor causes said power supply to transition from said second power supply state to said first power supply state responsive to said power management processor detecting a ring signal having a frequency in a predetermined range for a predetermined period of time; and   (4) wherein, during a transition from said power conservation mode to said normal operating mode,   responsive to a transition to said first power supply state caused by said power management processor detecting a ring signal having a frequency in a predetermined range for a predetermined period of time, and   before the state of the computer system is read from said non-volatile storage device, said CPU queries said modem whether said modem detects a ring signal, and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.       
     
     
       7. A computer system having at least two modes of power management, namely (i) a normal operating mode in which code is executed normally by the computer system, (ii) a power conservation mode in which the computer system consumes less electrical power than in said normal operating mode, said computer system comprising: (a) a CPU;   (b) a power management processor in circuit communication with said CPU, said power management processor causing transitions between said at least two modes of power management;   (c) a modem in circuit communication with said power management processor via a ring signal line and in circuit communication with said CPU, said modem for being placed in circuit communication with a telephone line, and said modem characterized by generating a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line;   (d) a fixed disk storage device in circuit communication with said CPU, said fixed disk storage device having therein a rotating storage medium, said storage medium having stored thereon the state of said computer system while said computer system is in said power conservation mode; and   (e) a power supply in circuit communication with said CPU and said power management processor, said power supply having circuitry for selectively providing system power to said CPU responsive to said power management processor and having auxiliary circuitry for providing auxiliary power to said power management processor, said power supply characterized by having a first power supply state and a second power supply state; wherein said first power supply state is characterized by said power supply providing system power to said CPU and providing auxiliary power to said power management processor; and   wherein said second power supply state is characterized by said power supply not providing system power to said CPU and said power supply providing auxiliary power to said power management processor;     (1) wherein transitioning from said power conservation mode to said normal operating mode includes said power management processor changing said power supply from said second power supply state to said first power supply state and, thereafter, reading the state of said computer system from said storage medium within said fixed disk storage device;   (2) wherein said power management processor analyzes the frequency of a ring signal generated by said modem;   (3) wherein said power management processor causes said power supply to transition from said second power supply state to said first power supply state responsive to said power management processor detecting a ring signal having a frequency in a predetermined range for a predetermined period of time; and   (4) wherein, during a transition from said power conservation mode to said normal operating mode,   responsive to a transition to said first power supply state caused by said power management processor detecting a ring signal having a frequency in a predetermined range for a predetermined period of time, and   before the state of the computer system is read from said storage medium within said fixed disk storage device, said CPU queries said modem whether said modem detects a ring signal, and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.       
     
     
       8. A computer system according to claim 6 wherein, during a transition from said power conservation mode to said normal operating mode,   responsive to a transition to said first power supply state caused by said power management processor detecting a ring signal having a frequency in a predetermined range for a predetermined period of time,   before the state of the computer system is read from said non-volatile storage device, and   during execution of a boot routine started responsive to said power supply transitioning from said second power supply state to said first power supply state and before said boot routine has completed execution, said CPU queries said modem whether said modem detects a ring signal, and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.     
     
     
       9. A computer system according to claim 7 wherein, during a transition from said power conservation mode to said normal operating mode,   responsive to a transition to said first power supply state caused by said power management processor detecting a ring signal having a frequency in a predetermined range for a predetermined period of time,   before the state of the computer system is read from said storage medium within said fixed disk storage device, and   during execution of a boot routine started responsive to said power supply transitioning from said second power supply state to said first power supply state and before said boot routine has completed execution, said CPU queries said modem whether said modem detects a ring signal, and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.     
     
     
       10. A computer system comprising: (a) a CPU;   (b) a power management processor in circuit communication with said CPU;   (c) a modem in circuit communication with said power management processor via a ring signal line and in circuit communication with said CPU, for being placed in circuit communication with a telephone line, and characterized by generating a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line;   (d) a power supply in circuit communication with said CPU and said power management processor comprising circuitry for selectively providing system power to said CPU responsive to said power management processor, characterized by having a first power supply state and a second power supply state, and further characterized by having circuitry for providing auxiliary power to said power management processor; wherein said first power supply state is characterized by said power supply providing system power to said CPU and providing auxiliary power to said power management processor; and   wherein said second power supply state is characterized by said power supply not providing system power to said CPU and said power supply providing auxiliary power to said power management processor;     (e) a fixed disk storage device in circuit communication with said CPU, said fixed disk storage device having therein a rotating storage medium, said medium having stored thereon a state of said computer system while said power supply is in said second power supply state, said rotating medium rotating at a predetermined rate while said power supply is in said first power supply state; and   (1) wherein said power management processor is further characterized by causing said power supply to transition from said first power supply state to said second power supply state responsive to at least one of a first predetermined plurality of conditions;   (2) wherein said power management processor is further characterized by causing said power supply to transition from said second power supply state to said first power supply state responsive to at least one of a second predetermined plurality of conditions;   (3) wherein one of said second predetermined plurality of conditions comprises a ring signal being communicated from said modem to said power management processor; and   (4) wherein, before said storage medium within said fixed disk storage device is rotating at the predetermined rate responsive to said power supply transitioning from said second power supply state to said first power supply state, said CPU queries said modem whether said modem detects a ring signal and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.   
     
     
       11. A computer system comprising: (a) a CPU;   (b) a power management processor in circuit communication with said CPU;   (c) a modem in circuit communication with said power management processor via a ring signal line and in circuit communication with said CPU, for being placed in circuit communication with a telephone line, and characterized by generating a ring signal on said ring signal line responsive to a telephone ring signal being present on said telephone line;   (d) a power supply in circuit communication with said CPU and said power management processor comprising circuitry for selectively providing system power to said CPU responsive to said power management processor, characterized by having a first power supply state and a second power supply state, and further characterized by having circuitry for providing auxiliary power to said power management processor; wherein said first power supply state is characterized by said power supply providing system power to said CPU and providing auxiliary power to said power management processor; and   wherein said second power supply state is characterized by said power supply not providing system power to said CPU and said power supply providing auxiliary power to said power management processor;     (1) wherein said power management processor is further characterized by causing said power supply to transition from said first power supply state to said second power supply state responsive to at least one of a first predetermined plurality of conditions;   (2) wherein said power management processor is further characterized by causing said power supply to transition from said second power supply state to said first power supply state responsive to at least one of a second predetermined plurality of conditions;   (3) wherein one of said second predetermined plurality of conditions comprises a ring signal being communicated from said modem to said power management processor; and   (4) wherein, during execution of a BIOS boot routine started responsive to said power supply transitioning from said second power supply state to said first power supply state and before said BIOS boot routine has completed execution, said CPU queries said modem whether said modem detects a ring signal and, responsive to said modem not detecting a ring signal, said CPU causes said power management processor to cause said power supply to transition back from said first power supply state to said second power supply state.